A variety of medical devices, for example, blood bags, blood oxygenators, blood dialyzers, venous reservoirs, and cardiotomy reservoirs, have inlet and ports through which fluids may be admitted to the interior of the device or through which fluids may be withdrawn from the device. Typically, these ports are relatively short lengths of hollow, more or less rigid plastic tubing which are sealed into one or more of the walls of the device. The protruding end of the port, which may include one or more tubing barbs, is used to receive conduit, e.g., flexible plastic tubing. Thus, for example a typical cardiotomy reservoir used as part of the extracorporeal blood circuit during cardio-pulmonary by-pass surgery comprises two or more inlet ports and at least one outlet port. A suction line or lines from the operative site may be attached to one or more of the inlet ports. In addition, pieces of tubing from sources of banked blood and other medical fluids are connected to other inlet ports. Another piece of tubing connects the blood outlet port of the cardiotomy reservoir to the inlet of a cardiotomy blood filter.
Medical devices of the kind mentioned above are sterilized by the manufacturer prior to delivery to the end-user. Prior to the sterilization operation the inlet ports and the outlet ports of the device are covered with port caps. Where, for example, the port on the device consists of a short piece of relatively rigid hollow plastic tubing, there is frictional engagement between the inner surface of the port cap and the outer surface of the plastic tubing. If the port on the device has the aforementioned tubing barbs, there is frictional engagement between the inner surface of the port cap and the outer surfaces of the outer edges of the tubing barbs. The aforementioned frictional engagement keeps the port cap in place and prevents entry of contaminating matter through the port into the interior of the device. In order to preserve the sterility of the inner surfaces of the device, the port caps are left in place over the various ports while the device is being unpacked and set up for use. The caps are removed when it is desired to expose the port so that suction tubing or fluid flow tubing, etc. may be connected thereto. The port cap, once it is removed, is not ordinarily used to again cover the port.
In some instances it may be necessary to add a measured amount of a medication to a medical device at the time it is to be used. For example, in the case of a cardiotomy reservoir it may be necessary to add an anti-coagulant prior to actual start-up of the surgical procedure. Such medication is usually added in relatively small amounts which must be measured accurately. A syringe is often used to accurately measure and dispense the desired medication. An ordinary inlet or outlet port is not suitable for this purpose because it is designed only to receive tubing and is not adapted to receive auxiliary medical equipment, such as a syringe, in a secure leak-proof manner.
Thus it would be quite advantageous to provide a port cap which could be removed in the usual way from a port of a device to expose said port for connection to suction tubing or fluid flow tubing or which, alternatively, could be used for the secure connection of auxiliary equipment to said port. Such a port cap would increase the versatility of the device and allow auxiliary equipment to remain securely connected to the medical device until it was time to use the same. The personnel using the device would have the option of using the port as an injection site as well as using it for the purpose of making flexible connections.